Technical Abstract:
The QTL affecting fat deposition on SSCX is well documented in Meishan x Western breed pedigrees. In two German Meishan derived families the QTL has been more pronounced in Wild Boar x Meishan (WxM, n = 335) than in Meishan x Piétrain (MxP, n = 316) pedigree and mapped between microsatellites SW259 and SW1943. To align human and porcine gene maps in this chromosome region orthologs of 10 genes from HSAXq13.1-q24 have been PCR cloned and sequenced. SNPs suitable for linkage analysis and porcine specific primers for RH mapping have been detected within 8 and 9 genes, respectively. Linkage mapping conducted on the USDA-MARC backcross and Hohenheim WxM and MxP pedigrees as well as RH mapping on IMpRH panel showed that RPS4X, XIST, POUSF4, FSHPRH1, SERPINA7, NOX1, ACSL4, CAPN6. PAK3 and HTR2C were located within the chromosome region. Though the gene orders on three linkage maps were in agreement with gene order on HSAX the RH mapping showed that minor rearrangement couldn't be excluded at the level of resolution used. Association analyses performed with detected SNPs showed that in WxM the highest association was found between fat cuts (%) and RPS4X (VF2 = 14.7%, F = 23.6, P < 0.0001) while in MxP surprisingly between lean cuts (%) and ACSL4 (VF2 = 16.6%, F = 26.9).